The present invention relates to a tool for facilitating the removal and fitting of tires on wheels.
In tire removal operations, specialized operators, after deflating the tires and placing them on the platform of a tire changing machine, use a contoured lever which is inserted between the tire beads and the wheel rims to lift said beads in at least one point of their circumference until they move past the peripheral rims of the wheels. This allows insertion of an appropriate tool supported by the operating arm of the tire changing machine, the extraction of the bead from the wheel being completed by turning the platform on which they are placed.
Once this operation has been completed, the specialized operator repeats the same operation for the opposite second bead, extracting it permanently from the wheel.
The above described removal operation is rather tiring for specialized operators, also because during a working day it is repeated several times and for small- and large-diameter wheels, which are increasingly often provided with tires that have rigid and shallow walls.
In order to be able to remove a tire easily, the tire must be first pressed on its walls so that the beads break away from the rim and are displaced centripetally on the wheel, toward its internal channel, which by having a smaller diameter than the lateral rims provides the clearance that allows to manipulate the tire until, as mentioned, it can move past the wheel rim that contains it laterally.
This pressure is applied by specialized operators in different manners, for example by using the bead lifting lever with which the machines are normally provided, in order to unseat the tires; said lever is used improperly as a presser, with the risk of damaging both the wheel, especially if it is coated with paints, and the intimate structure of the shoe of the tire, with consequent severe danger for the user of the vehicle.
Another method of applying said pressure is entirely manual and relies on mere physical strength: in this case, the operation, when possible, is in any case very demanding for operators, especially due to the unquestionable repetitiveness with which it must occur.
Likewise, during fitting, the tire, after being placed manually on the wheel, must be fitted completely thereon by reinserting the lower bead first and then the upper one.
In this reinsertion operation, operators again use said lever to insert a first initial portion of the bead of the tire beyond the rim of the wheel until it reaches the groove of said wheel and then, by using the turret of the machine combined with the rotation of the platform on which the wheel is clamped, complete the circumferential reinsertion of the bead.
In this operation, however, under the action of a gradually increasing traction of the inner edge of the tire while it is being fitted on the wheel, if no proper pression is exerted at the initial point of insertion of the bead, the latter spontaneously escapes from the rim, thwarting the entire operation, which must therefore be repeated from scratch.
The aim of the present invention is to eliminate the above noted drawbacks of the prior art by providing a tool for facilitating operations for removing and fitting tires on wheels that allows to apply the necessary pressure to the walls of the tires both for removing them and for fitting them in a practical manner and with minimal physical commitment, without damaging the wheel and the structure of the tire.
Within this aim, an object of the present invention is to provide a structure that is simple, easy to provide in practice, safe in use, effective in operation, and most of all relatively low in cost.
This aim and this and other objects that will become better apparent hereinafter are achieved by the present tool for facilitating operations for removing and fitting tires on wheels, characterized in that it consists of a lever element provided, at one end, with a grip and maneuvering region and, at the opposite end, with a resting and fulcrum means for resting on the wheels and for acting as a fulcrum and with a spacer means for mutually spacing the wheel rims and the tire beads that can be wedged between them.